Gene expression profiling of transcription factors associated with resistance to Sclerotinia basal stem rot disease in sunflower

basal stem rot is an important fungal disease of sunflower. It reduces growth and crop yield worldwide. The aim of this study is identification of resistant lines and confirmation of the accuracy of QTL analysis done for resistance to this disease in previous research in order for their use in sunflower breeding programs. In this study the expression of transcription factors (AP2 Domain, HD-Zip and MYB Family) responsible for resistance to disease was studied in susceptible (RHA265) and resistant (LC106-C) sunflower lines challenged with Sclerotinia fungal isolate (SSU53) using Real Time PCR. The results showed that the expression of the studied transcription factors is different in resistant and susceptible sunflower lines. In particular, expression of the AP2 domain and MYB Family increased significantly in resistant line LC106-C as compared to a susceptible one (RHA265). The results suggest a positive role of AP2 domain and MYB Family in resistance mechanisms of sunflower plant in response to Sclerotinia fungal disease. According to these results, the line LC106-C can be used as a resistant line for resistance to Sclerotinia disease. In addition, the highest expression level of genes in the resistant line compared to susceptible one confirmed the phenotypic data used in QTL analysis in our previous research. The findings of this study should be useful in sunflower breeding programs for producing cultivars resistant to disease.